Fuse for land mines



0r.14, 1947. F, SHORT 2,428,817

FUSE FoR LAND MINES Fi1e`d Jan. 25, A1945 8 E'iEJI- RIT 9 9 a. Wwf fm@ Patented Oct. 14, 1947 UNITED STATES PATENT FFICE FUSE FOR LAND MINES Frank Short, Canton Center, Conn.

Application January 25, 1945, Serial No. 574,599 7 11 claims. (orina- 7862) 7 (Granted under the act of March 3, 1883, as

amended April 30, 1928; 370 O. G. 757) The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment to me of any royalty thereon.

This invention relates to improvements in fuses for land mines.

It is a primary aim of this invention to provide a combination type fuse employing a single spring for projecting the ring pin and for holding the ring pin in a cocked or armed position.

Other objects of the invention are to provide novel arrangements of cam surfaces for coacting with the firing pin spring to retain the iiring pin in a cocked position; to provide a fuse capable of being released either by a pressure force or a pulling force; to provide a novel cam arrangement for releasing the fuse by a pressure force exerted in a direction coincident with the longitudinal aXis of the fuse; to provide a novel safety element which functions to prevent the accidental release or discharge of the fuse and which, in addition, assists in causing the fuse to release effectively, only when the iiring pin is correctly disposed to be projected.

Other objects and advantages of the invention will hereinafter become more apparent from the following description of the drawing which illustrates a preferred embodiment of the invention, and wherein:

Figure 1 is a longitudinal, substantially central sectional view, partly in elevation, showing the fuse in cocked position;

Figure 2 is a longitudinal, substantially central sectional View, partly in elevation, taken at right angles to Figure 1 and substantially along the plane of the line 2--2 of Figure 1;

Figure 3 is a fragmentary sectional View similar to Figure 1 and showing a firing pin in a released position about to be projected by its spring;

Figure 4 is a cross-sectional view of the fuse taken substantially along the plane as indicated by the line 4 4 of Figure l;

Figure 5 is a view similar to Figure 3 showing the fuse in a partially released position and with the firing pin being actuated by a pressure force; and

Figure 6 is a cross-sectional View of the fuse taken substantially along a plane as indicated by the line 6 6 of Figure 3.

Referring more particularly to the drawing, wherein like reference characters designate like or corresponding parts throughout the different views I designates generally the improved fuse in its entirety and including a housing, designated,

generally 3 formed'of a barrel 9, a casting portion I0 and a cover I I.

The barrel 9 is of the conventional type cornmonly used` in land mine 7fuses which is provided with an internally threaded outer end which is adapted to be connected to a conventional fuse base, not shown, which carries the primer or percussion cap. The opposite end of the barrel 9 is secured to a restricted end of the casting I by any suitable means such as a pressed fitting, as indicated at I2.

The casting I0 is provided with a bore designated generaly I3 which extends lengthwise therethrough and which is provided with a restricted inner end I4, which opens into the bore of barrel 9, and which is elliptical in cross-section, as best seen in Figure 6. A firing pin I5 extends through a substantial portion of both the barrel 9 and the casting IS and has a portion of its shank disposed in the elliptical bore portion I. The firing pin I5 is provided with a tapered end IS, disposed within the barrel 9 and which is adapted to engage and re the aforementioned Percussion cap or primer, not shown. Adjacent said tapered end I6, the ring pin I5 is provided with oppositely disposed, outwardly projecting ears I'l forming abutments for a washer I8 which is removably mounted on the iiring pin shank and which is provided with oppositely disposed, upwardly offset portions I9 for engaging the ears I1 to prevent rotation of the washer .I8 on the firing pin shank. An expansion spiral spring 2U is carried by the ring pin I 5, and within the barrel 9, and has o-ne end thereof bearing against the casting I0 and its opposite end seated on the washer I8, for urging ring pin I5 inwardly of or toward the barrel 9. The firing pin i5 is provided with a cone-shaped head 2| at its opposite end the under side of which is dished around the firing pin shank to form an annular dished shoulder 22.

The upper portion of the bore I3, in which the headed end 2| of the ring pin is disposed, is substantially enlarged. Casting Ii! is provided with an upwardly, outwardly inclined shoulder 23 which extends into the upper portion of the bore I3 and the inclination of which corresponds to that of the annular shoulder 22, to provide a 4detent to receive and engage a, portion of the shoulder 22, As best seen in Figure l, said engaging surfaces 22 and 23 are substantially ush, for a purpose which will hereinafter become apparent. The bore portion I3 is also provided with oppositely disposed, corresponding recesses 24 forming rests or seats for the depending legs 3 26 of an arch member 25. Arch member 25 is provided with an upper portion 21 which is tapered toward its outer end and which is angularly disposed relative to the legs 2G. With the ring pin I5, as seen in Figure l, with the shoulder 22 engaging the detent 23, the arch member 25, which formsa 'secondary'detentwill vbe 'disposed with'its'legs seated in the recesses 24 and with its upper portion 21 engaging ilush against the shank of the ring pin I and With the upper edge or free end of portion 21 engaging underva portion of the annular shoulder 22.

Casting I0 is provided with a relatively wide opening 23 which communicates lwith the bore I3, justnabove the bore portion I4 toV slidably receive a ring pin actuating bar one endof which is slidably disposed in the bore I3, and the opposite end of which is etxeriorly.disposedfrelative to casting I9 and bent upwardly relatively to said first mentioned end. Said last mentioned end, designated V3l) is providedfwithfan` eye tolwhich is connected an end of a trip wire'I. The rst mentioned end ofthe'bar 29 is-provided with a substantially circularopening 5I Ethrough which the firing pin shankllooselyfextends,"and as seen in-Figure--Bgtherbar 29 is alsoprovided'with oppositelyv disposedV notches 32 whichopenintothe `openingSI toperniitthepassage therethrough of theears I-`1. The-washer Itis provided with similar notches -I8, 4for detachabl-y-mounting-it on the ring pin shank. Between the opening 3I and its 4uptu'rned lend 30, bar J'28 is `provided with astruckf-upvtongue 3S-for engaging the wal1 of the bore-I3 to limit'the out-ward movement of the bar 29 `relative to casting I 9, 'for the purpose member 36 `vvlfiich is 'disposed therein,-in an in- `f verted positicnand whieh'has its enlargedend `extending vinto lthe outer fend of the bore t3. When the ringpin 'I5fis'fin'a cocked position, as seen. inlFigurefl; the'- round end of itseonical head "2li extends into a hollow interior of? the cone Y36 f fandbears against fa-portionvof the inclined wall "thereof, 'of antennae '31, :preferably '3, which are-suitably `bonded or otherwise secured at corresponding rends f thereof to the outsidewall-'ofthecover 'II 'Cover ''I 'is provided with -a plurality and which projectupwar'dly therefrom, for a purposewhich will hereinafter be "described,

Casting I9 is provided withalined openings 38 which `open vintothe bore I=3` and through which extend a cotter pin 39.

Cotterpin 39 engages a portion of the conical head 2l, as seen in Figure '1, to provide a positive safety to prevent ring ofithe fuse 1 until saidpositive safety-has been removed.

From the foregoing'it will be apparent that a conventional fuse base can be screwecl'into the outer end of thebarrel 9 and theconventional threaded well of an anti-personnel oranti-tank `mine for attaching the `fuse v"l thereto. The fuse 1 isepreferably disposed in an-uprlght Yposition as illustrated in the drawing and is concealed by 'being buried so that only the antennae 31 protrude from'theground 'and these are preferably =camou`aged with any available foliage, con- Yforming to the existing foliage, such 'as leaves.

"connected to the eye of the cotter pin to thereby fullyfarmtthe fuse 1. As previously stated fuse '1 is of the combination type which may be actufated eitl'rer :by an outward pull on the bar 29 vthrough Athe .wire 3l or by a downward pressure on one or more of the antennae 31. The elliptical bore t4 permits a suilicient oscillation of the iring pin shank to permit the firing pin to move i from its position-of'Figure 1 to its released posi- 'iiring pin I5.

tion of Figure?. Assuming a pull to be exerted on the bar 29, ring pin I5 will move from its cocked position of Figure 'r1 :toward :its released position-'ofFigure 3 withzthef shoulders -122 randl23 forming cam surfaces. .:Aszthis'movementoccurs the arch 25 will rock on .itsilegs '2f6mvhich pivot in the recesses v211 .duetoztheiring :pin :shank hearing against the apex of the archf2-5to thereby swingthe upper, freeendzofztheportion 2'1 outwardly"1elatively`tofthe annular shoulder-2:2. As this occurs'the free end ofzthep'ortion 21, dueto theVincline-'oi'thefshoulder22, will tend to raise thebonical head 2'I 'against "the action fof the spring 29 v"to Vlift lthe -'shoulder ..212 Aupward-ly :and away i from the: detent23 :.to'fassist inaefiectingthe iscn'gagement fromthez-detent. As the ring; pin treaches apositiomsubstantially axially of the fuse '1V as seenfin Figure: 3,v therupwardf end 21 .of thexarch;25-wil1.kick out from beneaththe annular `shoulder j22 topermit" the-spring V2l] `to project the firing vpin I5 :downwardly :so that ,its tapered end '1E lwillfengagethe percussion capP or primer vwhich :is disposed directly therebeneath for zthus firingV the :percussion cap and the. mine connected totheuse. Likewisezit ywi1l-be noted, that as the firing pin I5 reaches a position normal to the :axis Lof -the fusey 1 fthe tongue v:11012611.33

.would-engage the-wallof1bore lf3 to prevent further outward movement;v other- 29 to thereby preventlthe barfrombeing'moved sufciently sothat it would combine with the casting IIltovbindthe sliding movement of the firing pin. If 4a'pressure is exerted suchas-byfa person stepping on-.onelor more of the antennae 31, downwardlyon cover II, said cover willslidedownwardly and inwardly relativelyto casting IQ. This will cause the inclined inner wall ofthe cone 3B Ithrough .camming engagement with the rounded end of the conical headZI to camsaidhead andthering pin i5 laterally from itswposition of Figure l to its position of FigureB, in 4the .manner-illustrated in Figure to thusrelease the vfiring pin I5, in the same manneras heretoforedescribed. -It will-be readily apparent that when-the fuse `1-is thus actuated by a pressure type force that the arch 25 will function in thesame-manner as when the firing pin is actuated by a pull through the bar 29. 'It will be noted that the spring 20 and washer i3 form a pivot for the oscillating motion of the It will also be apparent that Vthe spring 2) not only functions to Aproject a ring pin but also acts to resiliently retain the `i-lring pin ina cocked positionJthrough cooperation with the cam surfaces`22 and 23 which are urged inwardly of each other by the spring. .It will be obvious thatthe fuse '1 willfunotion, although not 'as efiently, if the `arch 25 vis omitted.

Various modifications and changes are contemplated and may be resorted to, as the invention has only been illustrated and described in a preferred form, which should not be construed as limiting the scope of the appended claims which broadly denne the invention.

I claim:

1. A fuse for land mines comprising a housing, a spring projected ring pin disposed in the housing, said housing having an elliptical open lng through which the shank of the pin extends, the housing having an inwardly projecting shoulder, the ring pin being provided with a shoulder for engaging the shoulder of the housing to retain the pin in a retracted, cocked position, and a trip bar through which the pin loosely extends, said trip bar being movable by a force exerted from the exterior of the fuse to move the pin laterally in the elliptical opening for disengaging the shoulder of the pin and housing to release the firing pin to be projected by its spring.

2. A fuse as in claim 1, said shoulders being correspondingly inclined in a direction so that the firing pin spring will yieldably urge the shoulders toward one another for yieldably resisting release of the ring pin.

3. A fuse as in claim 1, said housing having a telescoping section to receive a pressure for moving the section inwardly of the housing, and said section and the ring pin having co-acting cam surfaces for disengaging said shoulders when the section is moved toward the housing.

4. A fuse for land mines comprising a housing having chambers in the ends thereof connected by an elliptical opening, a spring actuated ring pin extending through the opening, said ring pin having a cone-shaped head provided with a dished underside forming an annular shoulder, a shoulder formed on the interior of the housing and forming a detent to engage a portion of the annular shoulder to retain the firing pin in a retracted, cocked position, said detent being shaped tp bear flush against the annular shoulder to provide co-acting surfaces which are urged into engagement by the ring pin spring, and means for moving the ring pin laterally for disengaging the detent and annular shoulder, to release the ring pin.

5. A fuse as in claim 4, and an arch-shaped member disposed in said housing for yieldably holding the pin in a retracted position, said arch having depending legs pivotally engaging a portion of the housing, the upper intermediate portion of the arch being bent to engage flush against the shank of the firing pin, and the upper edge of the arch being disposed against the annular shoulder, whereby a lateral force exerted on the ring pin, to move it toward a released position, will be yieldably resisted by a rocking movement of the arch, away from the ring pin, to initially retract the iiring pin, against the action of its spring, to disengage the annular shoulder from the upper edge of the arch and from the detent to permit movement of the ring pin to a released position.

6. A fuse as in claim 4, and a blade extending into and slidably i engaging the housing and adapted to be connected to a trip wire, said firing pin slidably engaging the blade, and said blade being movable, by a rpull thereon, to move the ring pin to a released position.

7. A fuse as in claim 4, and a safety pin removably disposed in said housing and engaging and holding the firing pin in a retracted, cocked position.

8. A fuse as in claim 4, a hollow cone-shaped member disposed on the cone-shaped head of the pin, and a cover in telescoping engagement with the housing and bearing against the coneshaped member, whereby a pressure on the cover will produce a camming engagement of the coneshaped member and head to cam the ring pin laterally to a released position.

9. A fuse as in claim 4, a hollow cone-shaped member disposed on the cone-shaped head of the pin, a cover in telescoping engagement with the housing and bearing against the cone-shaped member, whereby a pressure on the cover will produce a camming engagement of the coneshaped member and head to cam the ring pin laterally to a released position, and antennae projecting outwardly from the cover for receiving a pushing force to move the cover inwardly of the housing. V

10. A fuse as in claim 4, a blade extending into and slidably engaging the housing and adapted to be connected to a trip wire, said ring pin slidably engaging the blade, and said blade being movable, by a pull thereon, to move the ring pin to a released position, a hollow cone-shaped member disposed on the cone-shaped head of the pin, a cover in telescoping engagement with the housing and bearing against the cone-shaped member, whereby a pressure on the cover will produce a camming engagement of the coneshaped member and head to cam the ring pin laterally to a released position, and antennae projecting outwardly from the cover for receiving a pushing force to move the cover inwardly of the housing.

11. A fuse for land mines comprising a housing, a iiring pin slidably and swingably mounted therein, co-acting shoulders on the firing pin and housing for holding the ring pin in a retracted, cocked position, a spring urging the firing pin toward a projected, released position, said shoulders having engaging surfaces inclined in a direction to cam the shoulders into engaging positions under the pressure of the spring, and means for displacing the firing pin laterally through an elliptical opening adapted to accommodate such lateral movement provided in said housing and through which the said ring pin extends to a released position.

FRANK SHORT.

REFERENCES CITED The following references are of record ln the file of this patent:

UNITED STATES PATENTS Number Name Date 1,675,118 Lucas June 26, 1928 FOREIGN PATENTS Number Country Date 440,082 Great Britain Dec. 19, 1935 124,493 Great Britain Apr. 3, 1919 

